Objectives: 1. Experiments to test whether Laughing Gull chicks can recognize their siblings individually. 2. Experiments to test influences of pre-hatching auditory experience on development of social responsiveness post-hatching in Laughing Gull chicks. 3. Ontogenetic study on behaviour in free living and captive Laughing Gull chicks. 4. Observation of breeding behaviour of Common Terns. 5. Observation of breeding behaviour of Black Skimmers. 6. Observation of predatory activities of foxes in the Brigantine Wildlife Refuge.